Quenching the Thirst for Potable Water Through Nanotechnology

After our last post discussing how experiments with carbon nanotubes (CNT’s) might greatly improve the effectiveness of reverse osmosis desalination now comes a new report from the Institute of Physics that shows researchers are getting closer to making this a reality. Already over a billion people do not have regular access to clean water and the problem will likely get worse as the demand for drinkable water is expected to grow dramatically in the near future. With natural sources increasingly scarce, this urgent need means there is an intense global interest in any potentially viable forms of water purification.

Right now the main issues preventing RO desalination on a large-scale basis are that the membranes used to perform seawater to freshwater separation do not remove salt ions with enough efficiency and they also require great amounts of energy (and therefore expense) in order to purify the water. Jason Reese, a Professor of Thermodynamics and Fluid Mechanics at the University of Strathclyde and also the author of this report, states, “The holy grail of reverse-osmosis desalination is combining high water-transport rates with efficient salt-ion rejection.” Incredibly, these little carbon nanotubes may be able to satisfy both of these requirements for widespread adoption.

Early tests and simulations have shown that CNT membranes could have water permeability that is 20 times greater than today’s materials. Additionally, carbon nanotubes can be chemically tailored to better reject salt ions, thus improving upon the desalination process in multiple key areas.

While it is still early, these features are promising enough that scientists such as Professor Reese feel it is a very real possibility that this application of nanotechnology could be used to curtail our growing water demand.